PMID- 17596338
OWN - NLM
STAT- MEDLINE
DCOM- 20070927
LR  - 20181113
IS  - 0027-8424 (Print)
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Linking)
VI  - 104
IP  - 28
DP  - 2007 Jul 10
TI  - Propagation of olfactory information in Drosophila.
PG  - 11826-31
AB  - Investigating how information propagates between layers in the olfactory system 
      is an important step toward understanding the olfactory code. Each glomerular 
      output projection neuron (PN) receives two sources of input: the olfactory 
      receptor neurons (ORNs) of the same glomerulus and interneurons that innervate 
      many glomeruli. We therefore asked how these inputs interact to produce PN 
      output. We used receptor gene mutations to silence all of the ORNs innervating a 
      specific glomerulus and recorded PN activity with two-photon calcium imaging and 
      electrophysiology. We found evidence for balanced excitatory and inhibitory 
      synaptic inputs but saw little or no response in the absence of direct ORN input. 
      We next asked whether any transformation of activity occurs at successive layers 
      of the antennal lobe. We found a strong link between PN firing and dendritic 
      calcium elevation, the latter of which is tightly correlated with calcium 
      activity in ORN axons, supporting the idea of glomerular propagation of olfactory 
      information. Finally, we showed that odors are represented by a sparse population 
      of PNs. Together, these results are consistent with the idea that direct receptor 
      input provides the main excitatory drive to PNs, whereas interneurons modulate PN 
      output. Balanced excitatory and inhibitory interneuron input may provide a 
      mechanism to adjust PN sensitivity.
FAU - Root, Cory M
AU  - Root CM
AD  - Division of Biological Sciences, University of California at San Diego, 9500 
      Gilman Drive, Bonner Hall 2206, La Jolla, CA 92093-0368, USA.
FAU - Semmelhack, Julia L
AU  - Semmelhack JL
FAU - Wong, Allan M
AU  - Wong AM
FAU - Flores, Jorge
AU  - Flores J
FAU - Wang, Jing W
AU  - Wang JW
LA  - eng
GR  - S06 GM008107/GM/NIGMS NIH HHS/United States
GR  - GM08107/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
DEP - 20070627
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Action Potentials/physiology
MH  - Animals
MH  - Brain/cytology/metabolism/physiology
MH  - Calcium/metabolism
MH  - Drosophila/*cytology/metabolism/*physiology
MH  - Interneurons/metabolism/physiology
MH  - Olfactory Receptor Neurons/metabolism/*physiology
MH  - Patch-Clamp Techniques
MH  - Smell/genetics/*physiology
PMC - PMC1913902
COIS- The authors declare no conflict of interest.
EDAT- 2007/06/29 09:00
MHDA- 2007/09/28 09:00
PMCR- 2008/01/10
CRDT- 2007/06/29 09:00
PHST- 2007/06/29 09:00 [pubmed]
PHST- 2007/09/28 09:00 [medline]
PHST- 2007/06/29 09:00 [entrez]
PHST- 2008/01/10 00:00 [pmc-release]
AID - 0704523104 [pii]
AID - 6791 [pii]
AID - 10.1073/pnas.0704523104 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2007 Jul 10;104(28):11826-31. doi: 
      10.1073/pnas.0704523104. Epub 2007 Jun 27.